COS-B Observations of Localised Gamma-Ray Emission
Bignami, G. F.; Hermsen, W.; Masnou, J. L.; Boella, G.; Bennett, K.; Buccheri, R.; Kanbach, G.; Lichti, G. G.; Mayer-Hasselwander, H. A.; Paul, J. A.; Scarsi, L.; Swanenburg, B. N.; Taylor, B. G.; Wills, R. D.; Higdon, J. C.
Netherlands, Italy, France, Germany
Abstract
The ESA gamma-ray satellite COS-B has completed a survey of the galactic plane. The long exposure time combined with the effective angular resolution of ~2.5 deg (FWHM) for gamma rays above 100 MeV permits a detailed study of the spatial distribution of the radiation. In four observation periods a search for localised gamma-ray emission has been performed. Each of the studied regions exhibits significant fine structure superimposed on a diffuse emission along the galactic plane. This fine structure is consistent with the presence of a large number of high-energy gamma-ray sources. A first catalogue, including 11 so far unidentified gamma-ray sources, is presented. The latitude distribution of these sources indicates a galactic nature.